1,4-Cyclohexadiene is an organic compound with the formula C₆H₈. It is a colourless, flammable liquid that is of academic interest as a prototype of a large class of related compounds called

terpenoid The terpenoids, also known as isoprenoids, are a class of naturally occurring organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeably with "terpenes" ...

s, an example being γ-

terpinene The terpinenes are a group of isomeric hydrocarbons that are classified as monoterpenes. They each have the same molecular formula and carbon framework, but they differ in the position of carbon-carbon double bonds. α-Terpinene has been isolate ...

. An

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

of this compound is 1,3-cyclohexadiene.

Synthesis and reactions

In the laboratory, substituted 1,4-cyclohexadienes are synthesized by

Birch reduction The Birch reduction is an organic reaction that is used to convert arenes to cyclohexadienes. The reaction is named after the Australian chemist Arthur Birch and involves the organic reduction of aromatic rings in an amine solvent (traditionally ...

of related aromatic compounds using an alkali metal dissolved in liquid ammonia and a proton donor such as an alcohol. In this way, over reduction to the fully saturated ring is avoided. 1,4-Cyclohexadiene and its derivatives are easily aromatized, the driving force being the formation of an aromatic ring. The conversion to an aromatic system may be used to trigger other reactions, such as the

Bergman cyclization The Masamune-Bergman cyclization or Masamune-Bergman reaction or Masamune-Bergman cycloaromatization is an organic reaction and more specifically a rearrangement reaction taking place when an enediyne is heated in presence of a suitable hydrogen do ...

.John C. Walton, Fernando Portela-Cubillo "1,4-Cyclohexadiene" Encyclopedia of Reagents for Organic Synthesis 2007 John Wiley & Sons.

References

External links

The photochemistry of 1,4-cyclohexadiene in solution and in the gas phase

''NIST Chemistry WebBook''
Reaction thermochemistry data {{DEFAULTSORT:Cyclohexadiene, 1,4- Cyclohexadienes